Coudé Auxiliary Telescope (decommissioned)

The ESO Coudé Auxiliary Telescope (CAT) was housed in a smaller dome, adjacent to the 3.6-metre telescope at ESO's La Silla Observatory, and fed the 3.6-metre's Coudé Echelle Spectrometer through a light tunnel. The CAT was fully computer controlled and was used for many different types of astronomical observations, including measuring the ages of ancient stars.